Dr Swetnam's work suggests that variations in temperature were well correlated with the frequency of fire during what climatologists call the medieval warm period, from 900 to 1300.

Swetnam博士的工作表明，在气象学家所说的中世纪暖期，即公元900年到1300年，气温的变动和火灾的频率密切相关。

youdao

Such "fire scars" in long-lived species like giant sequoias allow him to estimate the past frequency of forest fires.

这些在长寿物种，如巨红杉中留下的火灾印迹，使得他能够估计过去森林火灾的频次。

youdao

Emergency fire and police calls are also logged and reported, and Mrs Babbage grows concerned about the frequency of aid responses to an elderly homeowner up the street.

突发火灾及警方传唤也会被记录和报告，而巴贝奇太太越来越关心对街上上了年纪的屋主的回应援助的次数。

youdao

Yes, of course fire trucks need a radio frequency.

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A. cease-fire in 1994, Clinton and senior aides stepped up the frequency of meetings with Protestant Unionist leaders who had long considered Washington biased toward a united Ireland.

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It is the one to whom others in trouble turn, hoping that we will pull their chestnuts out of the fire, and we have been doing that with some frequency.

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